Gaia Data Release 4 (Gaia DR4)

The original Gaia DR4 data will become available from the Gaia ESA Archive. The expected content of Gaia DR4, pending certain processing and validation activities, is described here and summarised in this table.

 

Significant changes compared to previous Gaia data releases

Gaia DR4 is different from previous data releases in several ways:

Number and data volume of tables and other products

Gaia DR4 will contain a large number and diversity of data products. Lower-level data such as the individual observations underlying the source-level catalogue parameters will be released as well. Consequently, the total data volume of Gaia DR4 is approximately 500 TB with the largest fraction associated to the lower-level products. The total data volume of Gaia DR3 is 10 TB.

Content of the main source catalogues

In contrast to previous releases, data will be published for all processed sources, which amount to about 2.8 billion sources in total.

The gaia_source table in Gaia DR4 contains a high-quality subset of about 2 billion of these sources that are considered to have both high-quality astrometry and photometry. With respect to previous data releases, the parameters in this table are now consolidated from several different processing modules such that the best-suited model has been applied for a given source (e.g., a binary-star model instead of the default single-star model as was the case in Gaia DR3).

The  gaia_source table in Gaia DR4 is complemented by the following four tables that contain the results from the dedicated processing pipelines for all sources:

  • all_source_astrometry: Results for all sources from the core astrometry pipeline
  • all_source_photometry: Results for all sources from the core photometry pipeline
  • all_source_rvs: Results for all sources from the core spectroscopy pipeline
  • all_source_flags: Compiles a selection of flags for each source published in the Gaia catalogue. 
  • ​​​​​​​sso_source: ​​​​​​​Results for solar system objects (SSO). These sources follow a dedicated processing path and do not appear in gaia_source.

 

Summary of expected tables in the Gaia DR4 archive

The columns of the table below have the following meaning:

  • Id: Identifier that will eventually map to the corresponding section in the data model documentation.
  • Data model chapter: Indicates the name of the data model chapter. The Gaia DR4 draft data model will be published in advance of the data release.
  • Gaia Archive Table Name: Indicates the table name in the Gaia ESA Archive.
  • Description: Description of the data set.
  • Category: Helps to distinguish between the different data sets.
  • New in DR4: Inidcates if the type of data was already published with Gaia DR3 or not. All data published with Gaia DR4 will be new, but some data product types have not been published before. These are indicated with "NEW". "NEW in Archive" marks products that were published elsewhere, e.g., on Cosmos, in previous releases.
  • Data level: Indicative data level of the product. Level 1 (DL1) corresponds to image data, i.e., CCD pixel/sample values. Level 2 (DL2) corresponds to epoch data, i.e., time-resolved processing results usually per CCD transit. Level 3 (DL3) corresponds to source-level data with summary results per celestial source. Level 4 (DL4) corresponds to derived quantities that incorporate astrophysical models and priors.
  • Label: Helps to distinguish between the different data sets.
  • Access: Identifies the location and protocol with which the data are served:
    • TAP: Table Access Protocol in the archive
    • DataLink: DataLink protocol in the archive
The content of this table is under development and changes can be expected. Last update: 17 December 2025.

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Id Data model chapter / GACS section Gaia Archive Table Name Description Category New in DR4 Data level Label Access
01.01 Gaia Data Release 4 gaia_source Sources considered to have both high-quality astrometry and high-quality photometry. In contrast to previous data releases, the parameters in this table are consolidated from several different processing modules. Main   DL3 General TAP
01.02 Gaia Data Release 4 gaia_source_lite A "light" version of the gaia_source table, containing less parameters per source, to allow quick access. Main   DL3 General TAP
01.03 Gaia Data Release 4 spurious_signal This table contains a variety of statistics and models which can help in the identification of scan-angle related (spurious) signals. Main NEW in Archive DL3 General TAP
02.01 All-source all_source_astrometry Astrometric parameters obtained for nearly all sources. The sole exceptions are the sources only recognized in the special crowded-fields processing (see the crowded field source and related tables), and the sources only recognized in the Source Environment Analysis (SEApipe). Main NEW DL3 Astrometry TAP
02.02 All-source all_source_flags Compiles a selection of flags of interest for each source published in the Gaia catalogue. Main NEW DL3 Classification TAP
02.03 All-source all_source_match Global cross-match table compiling all source_id associations between those in all_source_astrometry, gaia_source_environment, and crowded_field_source. Main NEW DL3 CrossMatch TAP
02.04 All-source all_source_photometry Photometric parameters in the G and, where applicable, BP and/or RP band obtained for nearly all sources except those in crowded_field_source and gaia_source_environment. Main NEW DL3 Photometry TAP
02.05 All-source all_source_rvs Parameters such as radial velocities, spectral line broadening, and Grvs magnitudes, derived from the Radial Velocity Spectrometer (RVS). Main NEW DL3 Spectroscopy TAP
02.06 All-source crowded_field_source_environment_match A cross-match table between the individual source lists coming from the Crowded Field and Source Environment analysis pipelines. Main NEW DL3 CrossMatch TAP
03.01 Astrometry epoch_astrometry Time series of astrometric data, i.e. individual astrometric measurements for all sources treated in the main astrometric processing. Epoch NEW DL2 Astrometry DataLink
03.02 Astrometry epoch_image Image data from the Gaia CCDs for all sources treated in the main astrometric processing. These are pre-processed and sky-projected individual CCD sample values. Epoch NEW DL1 Image DataLink
04.01 Astrophysical parameters ap_chem Abundances of chemical elements of stars derived from mean RVS spectra by the General Stellar Parametrizer - Spectrometry (GSP-Spec) module. Main   DL4 Parameters TAP
04.02 Astrophysical parameters ap_class Classification probabilities and astrophysical parameters of sources derived by Discrete Source Classification (DSC), Outlier Analysis (OA), and Unsupervised Classification Analysis (UCA). Main   DL4 Classification TAP
04.03 Astrophysical parameters ap_class_ir Classification probabilities and parameters of sources derived by Discrete Source Classification (DSC) using Gaia data and external infrared photometry. Main NEW DL4 Classification TAP
04.04 Astrophysical parameters ap_emission Astrophysical properties of emission-line or active stars derived with the Extended Stellar Parametrizer Cool Stars (ESP-CS) and the Extended Stellar Parametrizer Emission-Line Stars (ESP-ELS) modules. Main   DL4 Parameters TAP
04.05 Astrophysical parameters ap_hot Astrophysical parameters of hot stars derived with Extended Stellar Parametrizer - Hot star (ESP-HS) module. Main   DL4 Parameters TAP
04.06 Astrophysical parameters ap_rvs Astrophysical parameters of stars derived from mean Radial Velocity Spectrometer (RVS) spectra with General Stellar Parametrizer - Spectrometry (GSP-Spec) and Final Luminosity, Age, and Mass Estimator (FLAME) modules. Main   DL4 Parameters TAP
04.07 Astrophysical parameters ap_rvs_epoch Astrophysical parameters, and in some cases the abundances, derived from the epoch Radial Velocity Spectrometer (RVS) spectra for RRLyrae and Cepheids with the General Stellar Parametrizer - Spectrometry (GSP-Spec) module. Epoch NEW DL4 Parameters TAP
04.08 Astrophysical parameters ap_xp Astrophysical parameters from mean BP/RP spectra derived with the Extended Stellar Parametrizer Ultra Cool Dwarfs (ESP-UCD), Extended Stellar Parametrizer Emission-Line Stars (ESP-ELS) , Generalised Stellar Parametrizer PHOTometry (GSP-Phot) and Final Luminosity, Age, and Mass Estimator (FLAME) modules. Main   DL4 Parameters TAP
04.09 Astrophysical parameters ap_xp_epoch Astrophysical parameters derived from the epoch RP spectra with Extended Stellar Parametrizer Ultra Cool Dwarfs (ESP-UCD) module. Epoch NEW DL4 Parameters TAP
04.10 Astrophysical parameters ap_xp_supp Astrophysical parameters from mean BP/RP spectra derived with Generalised Stellar Parametrizer PHOTometry (GSP-Phot). Each source has been analysed with three different stellar libraries and all of these results are published in this table. Main   DL4 Parameters TAP
04.11 Astrophysical parameters interstellar_medium_params Diffuse Interstellar Band (DIB) parameters derived from stacked spectra with DIB-Spec module; binned in galactic latitude, longitude, and distance. Main   DL4 Parameters TAP
04.12 Astrophysical parameters interstellar_medium_spectra Stacked Interstellar Medium Spectra as derived with DIB-Spec module; binned in galactic latitude, longitude, and distance. Main   DL4 Spectra TAP
04.13 Astrophysical parameters mcmc_samples_gsp_phot Parameter distributions from Markov Chain Monte Carlo (MCMC) chain of the Generalised Stellar Parametrizer PHOTometry (GSP-Phot) module. Main   DL4 Parameters DataLink
04.14 Astrophysical parameters oa_neuron_information Each entry corresponds to parameters estimated for one particular neuron of the Self-Organised Map using the Outlier Analysis (OA) module. Main   DL4 Parameters TAP
04.15 Astrophysical parameters oa_neuron_xp_spectra Prototype BP/RP spectrum for a particular neuron given in the oa_neuron_information table. Main   DL3 Spectra TAP
04.16 Astrophysical parameters total_galactic_extinction_map Total Galactic Extinction (TGE) map for the monochromatic extinction at 542.9 nm. Main   DL4 Parameters TAP
04.17 Astrophysical parameters total_galactic_extinction_map_opt This table provides an optimum version of the Total Galactic Extinction map for the monochromatic extinction at 542.9 nm, at a single HEALPix level 9. Main   DL4 Parameters TAP
04.18 Astrophysical parameters training_sources_dsc Sources used in training the Apsis/DSC (Discrete Source Classifier) module. Main NEW DL3 Parameters TAP
04.19 Astrophysical parameters training_sources_uca_oa Reference sources used by the UCA and OA modules as part of the Apsis processing chain. Main NEW DL3 Parameters TAP
04.20 Astrophysical parameters uca_neuron_information Each entry corresponds to parameters estimated for one particular neuron of the Self-Organised Map using the UCA module. Main NEW DL4 Parameters TAP
04.21 Astrophysical parameters uca_neuron_xp_spectra Prototype BP/RP spectrum for a particular neuron given in the uca_neuron_information table. Main NEW DL3 Spectra TAP
05.01 Auxiliary bam_observation Data from the Basic-Angle Monitor (BAM), i.e. from the on-board metrology interferometer designed to continually measure the variations of the effective angle between the viewing directions of the two Gaia fields of view. Auxiliary NEW DL1 Image TAP
05.02 Auxiliary commanded_scan_law Representation of the Gaia scanning law over the 66 month time period covered by the Gaia Data Release 4 including the Ecliptic Pole Scanning at the beginning of the mission. Auxiliary     General TAP
05.03 Auxiliary gaia_gap This table lists all time intervals excluded from the astrometric, photometric and/or spectroscopic data processing of the Gaia observations. Gaps are time periods where such observations have been ignored in the various processing pipelines. Auxiliary NEW in Archive   General TAP
05.04 Auxiliary gbot_observation Ground-based position measurements of the Gaia satellite taken by the Ground-Based Optical Tracking (GBOT) project for the purpose of Gaia orbit reconstruction. Auxiliary NEW   General TAP
05.05 Auxiliary onboard_detection_af_xp Object logs for the astrometric field and the BP and RP fields, corresponding to on-board detections in the sky mapper. This table contains low-precision coordinates that correspond to the assigned window centre. Epoch NEW DL1 Astrometry TAP
05.06 Auxiliary onboard_detection_rvs Object logs for the radial velocity spectrometer (RVS) field, corresponding to on-board detections in the sky mapper. This table contains low-precision coordinates that correspond to the assigned window centre. Epoch NEW DL1 Astrometry TAP
06.01 Bright stars bright_source_astrometry Astrometric parameters of 49 of the 51 brightest stellar sources in the sky, obtained using a special observation mode and special data processing methods. Main NEW DL3 Astrometry TAP
06.02 Bright stars bright_source_epoch_astrometry Time series of astrometric data, i.e. the individual astrometric measurements for the same 49 among the 51 brightest stars for which the astrometric parameters are presented in the bright_source_astrometry table. Epoch NEW DL2 Astrometry DataLink
07.01 Cross match catwise2020_best_neighbour List of matched Gaia DR4 objects with their best neighbour in the external catalogue. Cross match NEW   CrossMatch TAP
07.02 Cross match catwise2020_neighbourhood All good neighbours for each matched Gaia DR4 object. Cross match NEW   CrossMatch TAP
07.03 Cross match dr3_neighbourhood Users wishing to look up the DR4 record for an astrophysical source identified in E/DR3 must not simply extract the record from DR4 having the same source identifier. Within the neighbourhood of a given DR4 source there may be none, one or (rarely) several possible counterparts in E/DR3 sources indicated by rows in this table. Cross match NEW   CrossMatch TAP
07.04 Cross match gaia_eso_survey_best_neighbour List of matched external catalogue objects with their best neighbour in Gaia DR4. Cross match NEW   CrossMatch TAP
07.05 Cross match gaia_eso_survey_join Convenience table to be used to join Gaia-ESO Survey catalogue with the cross-match results. Cross match NEW   CrossMatch TAP
07.06 Cross match gaia_eso_survey_neighbourhood All good neighbours for each matched Gaia-ESO Survey object. Cross match NEW   CrossMatch TAP
07.07 Cross match hipparcos2_best_neighbour List of matched external catalogue objects with their best neighbour in Gaia DR4. Cross match     CrossMatch TAP
07.08 Cross match hipparcos2_neighbourhood All good neighbours for each matched Hipparcos2 object. Cross match     CrossMatch TAP
07.09 Cross match panstarrs1_best_neighbour List of matched Gaia objects with their best neighbour in the external catalogue. Cross match     CrossMatch TAP
07.10 Cross match panstarrs1_join Convenience table to be used to join Pan-STARRS1 DR1.1 catalogue with the cross-match results. Cross match     CrossMatch TAP
07.11 Cross match panstarrs1_neighbourhood All good neighbours for each matched Gaia DR4 object. Cross match     CrossMatch TAP
07.12 Cross match ravedr6_best_neighbour List of matched external catalogue objects with their best neighbour in Gaia DR4. Cross match     CrossMatch TAP
07.13 Cross match ravedr6_join Convenience table to be used to join RAVE DR6 catalogue with the cross-match results. Cross match     CrossMatch TAP
07.14 Cross match ravedr6_neighbourhood All good neighbours for each matched RAVE DR6 object. Cross match     CrossMatch TAP
07.15 Cross match sdssdr13_best_neighbour List of matched Gaia DR4 objects with their best neighbour in the external catalogue. Cross match     CrossMatch TAP
07.16 Cross match sdssdr13_join Convenience table to be used to join SDSS DR13 catalogue with the cross-match results. Cross match     CrossMatch TAP
07.17 Cross match sdssdr13_neighbourhood All good neighbours for each matched Gaia DR4 object. Cross match     CrossMatch TAP
07.18 Cross match skymapperdr2_best_neighbour List of matched Gaia DR4 objects with their best neighbour in the external catalogue. Cross match     CrossMatch TAP
07.19 Cross match skymapperdr2_join Convenience table to be used to join the SkyMapper DR2 catalogue with the cross-match results. Cross match     CrossMatch TAP
07.20 Cross match skymapperdr2_neighbourhood All good neighbours for each matched Gaia DR4 object. Cross match     CrossMatch TAP
07.21 Cross match tmass_psc_xsc_best_neighbour List of matched Gaia DR4 objects with their best neighbour in the external catalogue. Cross match     CrossMatch TAP
07.22 Cross match tmass_psc_xsc_join Convenience table to be used to join 2MASS PSC+XSC catalogue with the cross-match results. Cross match     CrossMatch TAP
07.23 Cross match tmass_psc_xsc_neighbourhood All good neighbours for each matched Gaia DR4 object. Cross match     CrossMatch TAP
07.24 Cross match tycho2tdsc_merge_best_neighbour List of matched external catalogue object with their best neighbour in Gaia DR4. Cross match     CrossMatch TAP
07.25 Cross match tycho2tdsc_merge_neighbourhood All good neighbours for each matched Tycho2tdscMerge object. Cross match     CrossMatch TAP
08.01 Crowded fields crowded_field_coverage_map Coverage maps of Crowded Fields. For each HEALPix cell covering the crowded field region the number of scans is given. Auxiliary NEW DL1 Image TAP
08.02 Crowded fields crowded_field_epoch_astrometry Time series of astrometric data, i.e. the individual astrometric measurements for the sources treated in the special crowded-field processing. Epoch NEW DL2 Astrometry DataLink
08.03 Crowded fields crowded_field_epoch_photometry Time series of photometric data, i.e. the individual photometric measurements for the sources treated in the special crowded-field processing. Epoch NEW DL2 Photometry DataLink
08.04 Crowded fields crowded_field_image Electronically de-biased and astrometrically calibrated images of crowded-fields published as FITS files. Image NEW DL1 Image DataLink
08.05 Crowded fields crowded_field_image_summary Metadata for electronically de-biased and astrometrically calibrated crowded field images published as FITS files. Main NEW DL1 Image TAP
08.06 Crowded fields crowded_field_source Sources created with the crowded-field image analysis pipeline. Main   DL3 General TAP
09.01 Extra-galactic galaxy_candidates Parameters derived from various modules dedicated to the classification and characterisation of sources considered as galaxy candidates. Galaxies   DL3 Parameters TAP
09.02 Extra-galactic galaxy_morphology_input_list List of input catalogues used to select any given source for which morphological analysis parameters are provided in the galaxy_candidates table. Galaxies   DL3 Classification TAP
09.03 Extra-galactic grav_lens_combination Information relevant at the level of a gravitational lens multiplet system analysed around lensed sources. Gravitational lensing   DL3 Parameters TAP
09.04 Extra-galactic grav_lens_component Potential gravitational lens components (including the quasars). Gravitational lensing   DL3 Classification TAP
09.05 Extra-galactic grav_lens_input_list List of input catalogues used to select any given source analysed by the Gravitational Lens module. Gravitational lensing   DL3 Classification TAP
09.06 Extra-galactic grav_lens_observation Observations used for gravitational lens search. Gravitational lensing   DL2 Classification TAP
09.07 Extra-galactic grav_lens_outlier Individual observations that have been discarded as outliers from the analysis of the gravitational lenses. Gravitational lensing   DL3 Classification TAP
09.08 Extra-galactic grav_lens_redshift Quasar and galaxy redshifts associated with an input list of quasars and lens components given in the corresponding gravitational lens component table. Gravitational lensing NEW DL3 Classification TAP
09.09 Extra-galactic grav_lens_xp_mean_spectrum Internally-calibrated mean BP/RP spectra of a given gravitational lens component in continuous representation. Gravitational lensing NEW DL3 Spectra DataLink
09.10 Extra-galactic qso_candidates Parameters derived from various modules dedicated to the classification and characterisation of sources considered as QSO candidates. Quasar   DL3 Parameters TAP
09.11 Extra-galactic qso_morphology_input_list List of input catalogues used to select those sources for which morphological analysis was performed in the QSO candidates table. Quasar   DL3 Classification TAP
10.01 Non-single stars nss_acceleration_astro Non-single-star (NSS) astrometric solution models for sources having a non-linear proper motion which is compatible with an acceleration solution. Non-single stars   DL3 Astrometry TAP
10.02 Non-single stars nss_epoch_flags Flags indicative of whether certain observations were used or not for the non-single stars processing. It can be used in combination with the epoch tables containing the astrometric, photometric or radial velocity data themselves. Epoch NEW DL2 General DataLink
10.03 Non-single stars nss_masses Masses derived from the non-single stars (NSS) solutions with orbital parameters. Non-single stars NEW in Archive DL4 Parameters TAP
10.04 Non-single stars nss_multiple_orbits Non-single-star orbital models for sources compatible with solutions having more than two bodies. Non-single stars NEW DL3 Astrometry TAP
10.05 Non-single stars nss_multiplicity Source may be involved in more than one resolved pair. This table list all pairs involving a given source. Non-single stars NEW DL3 Astrometry TAP
10.06 Non-single stars nss_non_linear_spectro Non-single-star orbital models for spectroscopic binaries compatible with a trend. Non-single stars   DL3 Spectroscopy TAP
10.07 Non-single stars nss_resolved_pair Non-single-star astrometric models for resolved pairs of sources being physically bound (in contrast with chance alignment pairs). Non-single stars NEW DL3 Astrometry TAP
10.08 Non-single stars nss_two_body_orbit Non-single-star orbital solution parameters for sources compatible with an orbital two-body solution. This covers astrometric binaries, spectroscopic binaries, eclipsing binaries and certain combinations thereof. Non-single stars   DL3 Astrometry TAP
10.09 Non-single stars nss_vim_fl Non-single-star solution parameters for sources compatible with a Variability-Induced Mover (VIM) solution. Non-single stars   DL3 Astrometry TAP
10.10 Non-single stars optical_pair Optical Pairs / chance alignment of spatially close sources. Main NEW DL3 Astrometry TAP
11.01 Performance verification To be defined Several tables will be published along with the Gaia Data Release Performance Verification Papers. More details will be provided later. Performance Verification NEW   General TAP
12.01 Photometry epoch_photometry Time series of photometric data aggregated per FOV-transit, i.e. the light curve at FoV level for a given source in the G, BP and RP bands. Epoch NEW DL2 Photometry DataLink
12.02 Photometry epoch_photometry_ccd Time series of photometric data at CCD-transit level, i.e. the light curve at FoV level for a given source in the G band. Epoch NEW DL2 Photometry DataLink
12.03 Photometry synthetic_photometry_gspc Synthetic photometry generated from the Gaia BP/RP mean spectra and standardised using wide and reliable sets of external standard stars. Provided in a selection of photometric systems. Main   DL4 Photometry TAP
13.01 Reference frame frame_rotator_source Sources used to compute the Gaia reference frame. Main   DL3 Reference Frame TAP
13.02 Reference frame gaia_crf4 Gaia Celestial Reference Frame (Gaia-CRF4) table. Main NEW DL3 Astrometry TAP
13.03 Reference frame gaia_crf4_external_names Full cross-match information for the Gaia Celestial Reference Frame (Gaia-CRF4) sources. The Gaia-CRF4 sources were selected from the cross-matches with external QSO catalogues. Main   DL3 CrossMatch TAP
14.01 Science alerts alerts_mixedin_sourceids List of identifiers for mixed-in sources for Gaia Photometric Science Alerts, where transits from the primary source are mixed with other sources in the catalogue. Main   DL3 Classification TAP
14.02 Science alerts science_alerts Gaia Photometric Science Alerts triggered in the time span covered by DR4, i.e. 25-07-2014 to 20-01-2020. Main   DL3 Classification TAP
14.03 Science alerts sso_alerts Transit IDs of observations that have have been associated with published asteroid alerts. Main   DL3 Classification TAP
15.01 Simulation gaia_source_simulation Gaia Simulations - Sources realised according to the Gaia Object Generator (GOG) simulation. Observed attributes are given with simulated observational uncertainties. Simulations     Simulations TAP
15.02 Simulation gum_galaxy Gaia Simulations (GUM Galaxies). Table of simulated unresolved galaxies according to the Gaia Universe Model Simulation (GUMS). Simulations NEW   Simulations TAP
15.03 Simulation gum_mw Gaia Simulations (GUM Milky Way). Table of simulated galactic stars according to the Gaia Universe Model Simulation (GUMS). Simulations     Simulations TAP
15.04 Simulation gum_qso Gaia Simulations (GUM QSO). Table of simulated QSOs according to the Gaia Universe Model Simulation (GUMS). Simulations NEW   Simulations TAP
15.05 Simulation gum_sn Gaia Simulations (GUM Supernovae). Table of simulated supernovae according to the Gaia Universe Model Simulation (GUMS). Simulations NEW   Simulations TAP
16.01 Solar system sso_observation Solar System objects (SSO) - observations. Each table row contains data obtained during the transit of the source on a single CCD, during a single transit. The corresponding epoch is provided. Epoch   DL2 General TAP
16.02 Solar system sso_reflectance_spectrum Solar system objects (SSO) - Mean BP/RP reflectance spectra of asteroids computed as the ratio between the asteroid flux and an averaged solar analogue flux. Solar System   DL3 Spectra TAP
16.03 Solar system sso_source Solar system objects (SSO) - sources. Data related to Solar System objects observed by Gaia. Quantities are related to single objects. Solar System   DL3 Parameters TAP
16.04 Solar system sso_xp_epoch_spectrum Solar system objects (SSO) - Epoch BP and RP spectra collected at transit level for SSO sources. Epoch NEW DL2 Spectra DataLink
17.01 Source environment gaia_source_environment Astrometry, photometry, and related information for sources detected by the SEAPipe processing in the surrounding of sources in the main Gaia source catalogue. Main NEW DL3 General TAP
17.02 Source environment residual_image Reconstructed 2-dimensional image centred on the source given by the source identifier. The 2D image is reconstructed from the window data from multiple transits. The central source has been removed from the image to allow the detection of other features. Main NEW DL3 Image DataLink
18.01 Spectroscopy rvs_epoch_parameters_double FOV-transit-level information for the radial velocity, spectral line broadening, and Grvs magnitudes for double-lined transits. Epoch NEW DL2 Spectroscopy DataLink
18.02 Spectroscopy rvs_epoch_parameters_single FOV-transit-level information for radial velocity, spectral line broadening, and Grvs magnitudes for single-lined transits. Epoch NEW DL2 Spectroscopy DataLink
18.03 Spectroscopy rvs_epoch_spectrum RVS spectra combined at the FOV-transit level. The spectra are in the solar barycentric frame and normalized. Epoch NEW DL2 Spectra DataLink
18.04 Spectroscopy rvs_mean_spectrum RVS mean sampled spectra. The spectra are in the rest frame and are normalised. Main   DL3 Spectra DataLink
18.05 Spectroscopy rvs_transit_description CCD level information for RVS transits. Epoch NEW DL2 Spectra TAP
18.06 Spectroscopy rvs_two_body_orbit Spectroscopic binary solutions derived from the analysis performed by the Line Integral Analysis (LIA) modules, using both the astrometric orbital solutions and the cross-correlation functions between RVS epoch spectra and synthetic spectral templates. Non-single stars NEW DL3 Spectroscopy TAP
18.07 Spectroscopy xp_continuous_mean_spectrum Mean BP and RP spectra based on the continuous representation in basis functions. Main   DL3 Spectra DataLink
18.08 Spectroscopy xp_epoch_crowding Information on both treated and untreated crowding for both BP and RP CCDs for a FoV transit. Epoch NEW DL2 Photometry DataLink
18.09 Spectroscopy xp_epoch_spectrum Epoch BP and RP spectra collected at transit level (with the exception of Solar System Objects (SSO) sources). Epoch NEW DL2 Spectra DataLink
18.10 Spectroscopy xp_summary Auxiliary information about the mean BP/RP spectrum of a given source. Main NEW DL3 Photometry TAP
19.01 Variability vari_agn Active galactic nuclei. Main   DL4 Variability TAP
19.02 Variability vari_cepheid Cepheids. Main   DL4 Variability TAP
19.03 Variability vari_classifier_feature Environment and period-search derived features used by the supervised variability classifiers. Main NEW   Variability TAP
19.04 Variability vari_classifier_result Variability classification results of all classifiers. Main   DL4 Classification TAP
19.05 Variability vari_compact_companion Compact companion candidates. Main   DL4 Variability TAP
19.06 Variability vari_eclipsing_binary Eclipsing binaries resulting from variability analysis. Main   DL4 Variability TAP
19.07 Variability vari_epoch_flags Flags indicative of whether certain observations were used or not for the variable stars processing VariPipe. It can be used in combination with the epoch tables containing the astrometric, photometric or radial velocity data themselves. Main NEW DL2 Variability DataLink
19.08 Variability vari_flaring_star Flaring star. Main NEW DL4 Variability TAP
19.09 Variability vari_gvd_classifier_feature Features used by the General Variability Detection (GVD) classifiers. Main NEW   Variability TAP
19.10 Variability vari_long_period_variable Long Period Variable stars. Main   DL4 Variability TAP
19.11 Variability vari_microlensing Microlensing events. Main   DL4 Variability TAP
19.12 Variability vari_planetary_transit Planetary transit candidate events. Main   DL4 Variability TAP
19.13 Variability vari_pms_oscillator Pre-main-sequence oscillators. Main NEW DL4 Variability TAP
19.14 Variability vari_rad_vel_statistics Statistical parameters of radial velocity time series. Main NEW DL3 Variability TAP
19.15 Variability vari_rotation_modulation Solar-like stars with rotational modulation. Main   DL4 Variability TAP
19.16 Variability vari_rrlyrae RR Lyrae stars. Main   DL4 Variability TAP
19.17 Variability vari_short_timescale Short-timescale variables. Main   DL4 Variability TAP
19.18 Variability vari_summary Information on where a source can be found in the different Variability tables and statistical parameters of timeseries, using only transits not rejected. Main   DL3 Variability TAP
19.19 Variability vari_unsupervised Various features computed from the unsupervised classification and clustering from the variability analysis. Main NEW DL4 Classification TAP
19.20 Variability vari_yso Young stellar objects. Main NEW DL4 Variability TAP

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Background of the data

Gaia DR4 data is based on data collected between 25 July 2014 (10:30 UTC) and 20 January 2020 (22:00 UTC) spanning a period of 66 months of data collection that includes the complete nominal mission. As a comparison, Gaia DR3 was based on 34 months of data, Gaia DR2 was based on 22 months of data, and Gaia DR1 was based on observations collected in the first 14 months of Gaia's routine operational phase.

The reference epoch for Gaia DR4 is J2017.5. Remember that the reference epoch is different for each Gaia data release, and that the reference epoch for Gaia DR3 was J2016.0, for Gaia DR2 was J2015.5, and for Gaia DR1 was J2015.0.

Positions and proper motions are referred to the ICRS, to which the optical reference frame defined by Gaia DR4 (Gaia-CRF4) is aligned. The time coordinate for Gaia DR4 results is the barycentric coordinate time (TCB).

 

Gaia Source Identifiers

Sources in the Gaia Catalogue are all identified through the Gaia Source Identifier, i.e., the source_id field in the various tables in the Gaia Archive. The construction of the source identifiers is explained in the archive documentation (for Gaia DR1, see the data model section). In particular, the source_id number contains rough information about the source position on the sky.

As explained in previous announcements, there are various reasons why the identifier of a specific source may change or disappear when going from the Gaia DR1 to the Gaia DR2 source list and on to the Gaia DR3 and Gaia DR4 source lists. Users of Gaia data should thus be aware that the source list for Gaia DR4 should be treated as independent from Gaia DR3, Gaia DR2, and from Gaia DR1. With each new Gaia data release, the source list is becoming progressively more stable.

The Gaia source names ('designations') for Gaia DR4 are all constructed as follows:

Gaia DR4 yyy....yy

 

Accessing the data

The Gaia ESA Archive will be the main point of access to the Gaia DR4 data, but the data (or a subset thereof) will also be served from our partner data centres (CDS, ASDC, ARI, AIP and Flatiron). Data can be extracted from the Gaia Archive by performing ADQL queries and downloading the corresponding results tables.

The total size will be about 500 TB, of which a large fraction is the level-2 (epoch) data.

 

Passbands

Gaia DR4 photometric passbands will be published to document how the Gaia DR4 magnitudes are computed, and to allow reproducing the analysis of the data.

 

Documentation

Data release documentation is provided along with each data release in the form of a downloadable PDF and a webpage, plus a set of Data Release papers describing the processing and performance of the catalogue. Please visit the Gaia ESA Archive support pages to access Gaia documentation, and make sure to go through all relevant information given from the documentation overview page.

 

Known issues with Gaia Data Release 4

A list of issues with the data or info given along with the data will be provided. In case you find an issue with the data yourself, please contact the Gaia Helpdesk to let us know.

 

Data model

The Gaia DR4 data model describes all tables together with the names and contents of the columns inside each table. This information will become available from the Gaia ESA Archive along with the data release documentation.

 

In advance of Gaia DR4, we will publish a draft version of the data model here.

 

Data Release papers

Along with the Gaia DR4 data release documentation, several data processing papers will be published describing the specifics of the data processing and validation performed by the different coordination units in the Gaia Data Processing and Analysis Consortium (DPAC). There will also be some papers on the performance verification of Gaia, providing basic demonstrations of the scientific potential of the Gaia DR4 catalogue. Some pre-release processing papers are already available.